android - Gradually increase/decrease animation speed? [Android]

Question

I was working on animated effect on android, I would like to know if there's any other way to gradually increase/decrease the animation speed?

Is it possible to specify like first 3 second rate of change was slow, and the rest goes fast?

Answer 1

使用插值器。对于您的情况，我会推荐AccelerateDecelerateInterpolator

Animation anim = AnimationUtils.loadAnimation(this, R.anim.your_animation);
anim.setInterpolator(new AccelerateDecelerateInterpolator());
image.startAnimation(anim);

至于插值器，你可以自己构建！

public class MyInterpolator extends Interpolator {

    public MyInterpolator(int valueCount) {
        super(valueCount);
    }

    public float getInterpolation (float input) {
        return (float)(Math.cos((input + 1) * Math.PI) / 2.0f) + 0.5f;
    }
}

使用Wolfram Alpha，您可以使用参数。